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Seven replication origins from resident plasmids of Bacillus thuringienis subsp. kurstaki HD263 and HD73 were cloned in Escherichia coli. Three of these replication origins, originating from plasmids of 43, 44, and 60 MDa, were used to construct a set of compatible shuttle vectors that exhibit structural and segregational stability in the Cry- strain B. thuringiensis HD73-26. These shuttle vectors, pEG597, pEG853, and pEG854, were designed with rare restriction sites that permit various adaptations, including the construction of small recombinant plasmids lacking antibiotic resistance genes. The cryIA(c) and cryIIA insecticidal crystal protein genes were inserted into these vectors to demonstrate crystal protein production in B. thuringiensis. Introduction of a cloned cryIA(c) gene from strain HD263 into a B. thuringiensis subsp. aizawai strain exhibiting good insecticidal activity against Spodoptera exigua resulted in a recombinant strain with an improved spectrum of insecticidal activity. Shuttle vectors of this sort should be valuable in future genetic studies of B. thuringiensis as well as in the development of B. thuringiensis strains for use as microbial pesticides. 相似文献
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Alvin H. Gold David Dickemper Doris M. Haverstick 《Molecular and cellular biochemistry》1979,25(1):47-59
Summary Liver glycogen synthase b phosphatase, chromatographically separable from phosphorylase a phosphatase, is decreased in 48-hour alloxan diabetic rats. The phosphatase activities are measured in an in vitro system using exogenous isolated phospho-enzyme as substrates with added phosphatases. Synthase and phosphorylase phosphatases were shown to have differential catalytic properties by their reactivity in the presence of Pi, the heat-stable inhibitor of phosphorylase phosphatase and after incubation with added cAMP-dependent protein kinase.Supported by NIH Grants HD-07788, AM-21149 and, in part, by grants from the Greater St. Louis Diabetic Childrens Welfare Association and the American Diabetes Association, N.Y. 相似文献
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An endopeptidase from the larvae of the hornet Vespa crabro has been purified to homogeneity. The enzyme has been characterized with respect to molecular weight, amino acid compositon, and amino- and carboxyl-terminal sequences. The catalytic properties of the hornet protease are similar to those of bovine chymotrypsin with respect to inactivation by phenylmethanesulfonyl fluoride and carbobenzoxyphenylalanine chloro ketone and preferential peptide bond cleavage at aromatic amino acid residues. In contrast to bovine chymotrypsin, the hornet protease is not inhibited by the basic pancreatic Kunitz inhibitor, soybean inhibitor, or chicken ovomucoid. The molecular weight, as determined by several independent methods, was found to be 14 500. The protease is a single-chain protein containing two disulfide bonds. The terminal sequences are: NH2-Ile-Val-Gly-Gly-Ile-Asp.....Gly-Lys-Tyr-Pro-Tyr-Gln-Val-Ser-Leu-Arg-COOH. 相似文献
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New nomenclatural combinations are validated for fifteen taxa belonging to the generaDanthonia, Stipa, Lolium, Phippsia, Elymus, Schoenoplectus andAllium. 相似文献
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Doris M. Odlum 《BMJ (Clinical research ed.)》1932,1(3729):1169-1171